Figure 1
From: Effects of ventilation strategy on distribution of lung inflammatory cell activity
Sokoloff model for 18F-fluorodeoxyglucose tracer kinetics [13]. The three compartments of the model describe the activity concentration of 18F-fluorodeoxyglucose (18F-FDG) in plasma (Cp(t)), the region of interest (ROI) concentration of extravascular 18F-FDG serving as a substrate pool for hexokinase (precursor compartment, Ce(t)) and the ROI concentration of phosphorylated 18F-FDG (Cm(t)). The arrows indicate the tracer exchanges in the dynamic model and the corresponding parameters. The rate constants k1 and k2 account for forward and backward transport of 18F-FDG between blood and tissue. k3 is the rate of 18F-FDG phosphorylation, reflecting hexokinase activity. The constant Fe represents the distribution volume of 18F-FDG (that is, the substrate pool for hexokinase) as a fraction of lung tissue volume.